Create a "utils" module

Also put configuration macros in a dedicated header. In the future the
configuration will be read at execution time.

1 files changed, 107 insertions, 0 deletions

diff --git a/src/utils.c b/src/utils.c
new file mode 100644
index 0000000..a1fc5b9
--- /dev/null
+++ b/src/utils.c
@@ -0,0 +1,107 @@
+#include <assert.h>
+#include <errno.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "config.h"
+#include "system.h"
+#include "utils.h"
+
+void __strbuild(char *buf, int size,
+		const char *file, int line,
+		const char *fmt, ...)
+{
+	va_list ap;
+	int len;
+
+	va_start(ap, fmt);
+	len = vsnprintf(NULL, 0, fmt, ap);
+	va_end(ap);
+
+	if (len < 0) {
+		fprintf(stderr, "%s:%d: ", file, line);
+		perror("");
+		exit(EXIT_FAILURE);
+	}
+	if (len >= size) {
+		fprintf(stderr, "%s:%d: error: not enough space, "
+			"have %d, need at least %d\n",
+			file, line,
+			size, len + 1);
+		exit(EXIT_FAILURE);
+	}
+
+	va_start(ap, fmt);
+	len = vsnprintf(buf, size, fmt, ap);
+	va_end(ap);
+
+	assert(len >= 0);
+}
+
+int str_has_suffix(const char *str, const char *suffix)
+{
+	int str_len = strlen(str);
+	int suffix_len = strlen(suffix);
+	return ((str_len > suffix_len)
+		&& (strcmp(str + str_len - suffix_len, suffix) == 0));
+}
+
+void assert_db_exists(void)
+{
+	if (file_exists(DATABASE_PATH))
+		return;
+
+	if (errno == ENOENT) {
+		fprintf(stderr,
+			"ftag: database not found at \"%s\", "
+			"have you run \"ftag init\"?\n",
+			DATABASE_PATH);
+	}
+	else {
+		perror(DATABASE_PATH);
+	}
+	exit(EXIT_FAILURE);
+}
+
+uint32_t sum(const char *file)
+{
+	FILE *stream = fopen(file, "r");
+	uint8_t buf[4096];
+	size_t buf_len;
+	uint32_t sum = 5381;
+	if (!file) {
+		fprintf(stderr, "fopen: \"%s\": ", file);
+		perror("");
+		exit(EXIT_FAILURE);
+	}
+	while ((buf_len = fread(&buf, 1, sizeof(buf), stream)) != 0) {
+		for (int i = 0; i < buf_len; i++) {
+			uint8_t next = buf[i];
+			sum = sum*33 + next;
+		}
+	}
+	if (ferror(stream)) {
+		fprintf(stderr, "fread: \"%s\": ", file);
+		perror("");
+		exit(EXIT_FAILURE);
+	}
+	fclose(stream);
+	return sum;
+}
+
+time_t time_from_str(const char *str)
+{
+	int rc;
+	struct tm tm;
+	memset(&tm, 0, sizeof(tm));
+	rc = sscanf(str, "%d-%d-%d", &tm.tm_year, &tm.tm_mon, &tm.tm_mday);
+	if (rc <= 0) {
+		perror("sscanf");
+		exit(EXIT_FAILURE);
+	}
+	tm.tm_year -= 1900;
+	tm.tm_mon -= 1;
+	return mktime(&tm);
+}